Nitto-denko Corporation

Yoshihide Kawaguchi

Yutaka Moroishi

Tetsuo Inoue

Fumiko Nakano

Katsumi Ishii

Kohei Yano

Noriaki Harada

Atsushi Hiro

Osamu Hayashi

Atsuko Mizuike

Yoshikazu Tanaka

Makoto Kojima

Kazunori Mune

Shunsuke Noumi

Hiroichi Ukei

Shuzo Fujiwara

Yoshio Nakagawa

Masato Shirai

Katsuhide Kojima

Hironori Tamai

It is an object of the present invention to provide a composite semi-permeable membrane exhibiting excellent chemical resistance and having practical water permeability and salt-blocking property, and a method for producing the same. The present invention relates to a composite semi-permeable membrane, including a porous support and a skin layer formed on a surface of the porous support, wherein the porous support contains a thermosetting resin porous sheet having a three-dimensional network structure and pores communicating with each other and wherein the thermosetting resin porous sheet has an average pore diameter of 0.01 to 0.4 &#x3bc;m.

Composite semi-permeable membrane and method for producing same

Disclosed is a method for easily producing a long porous thermosetting resin sheet which has no resin coating film on the surface. Also disclosed are a porous thermosetting resin sheet produced by the method, and a composite semipermeable membrane having excellent chemical resistance and practical water permeability and salt-blocking property. The porous thermosetting resin sheet can be produced by forming a cylindrical or columnar resin block which is composed of a cured product of a thermosetting resin composition containing a thermosetting resin, a curing agent and a porogen; then forming a long thermosetting resin sheet by cutting the surface of the resin block at a certain thickness; and then removing the porogen from the thermosetting resin sheet.

Method for producing porous thermosetting resin sheet, porous thermosetting resin sheet and composite semipermeable membrane using same

Provided are a pressure sensitive adhesive composition for optical members and a pressure sensitive adhesive composition for optical members. The pressure sensitive adhesive composition for optical members according to the present invention comprises 100 parts by weight of an acrylic polymer (A) having a weight-average molecular weight of 500,000 or more, containing at least 50 wt % alkyl (meth)acrylate having an alkyl group with 5 or more carbon atoms and 0.2 to 2 wt % unsaturated carboxylic acid as the monomer unit, 0.1 to 4 parts by weight of an acrylic polymer (B) having a weight-average molecular weight of 2,000 to 50,000, containing at least 70 wt % alkyl (meth)acrylate and 1 to 7 wt % unsaturated carboxylic acid as the monomer unit and having a higher carboxylic acid equivalent than that of the acrylic polymer (A), 0.01 to 1 part by weight of a silane coupling agent, and a crosslinking agent.

Pressure sensitive adhesive composition for optical members, pressure sensitive adhesive layer for optical members, pressure sensitive adhesive optical member and image display

The present invention provides a hologram recording material which can modulate its refractive index effectively with visible light laser and is excellent also in transparency after this modulation. The present invention relates to a hologram recording material comprising a polymer (A) having a radically polymerizable side chain vinyl group in the molecule thereof, said polymer (A) being a polymer of monomers comprising as an essential component an acryl-vinyl monomer represented by the following formula (1):CH&#x2550;C(R)C(&#x2550;O)O&#x2014;R&#x2550;CH&#x2003;&#x2003;(1)wherein Rrepresents a hydrogen atom or methyl group, and Rrepresents a saturated or unsaturated hydrocarbon group having 1 to 20 carbon atoms, which may contain hetero atoms or halogen atoms in the molecule thereof; and a photopolymerization initiation source (B) which generates an active seed by visible light, and particularly relates to a hologram recording material having the aforementioned constitution in which the aforementioned photopolymerization initiation source (B) is a photopolymerization initiator which absorbs visible light to generate an active seed or a mixture of visible light-sensitizing dye and photopolymerization initiator.

Hologram recording material

The present invention provides an optical refractive index-modifying polymer composition which can efficiently modulate (change) refractive index upon light irradiation, and exhibits such high storage stability that the once modulated refractive index does not substantially change anymore upon time elapse, and the optical refractive index-modifying polymer composition comprises as a main component a polymer (A) which is a polymer of monomers including an acrylic vinyl monomer represented by the following formula (1):CH&#x2550;C(R)&#x2014;C(&#x2550;O)O&#x2014;R&#x2550;CH&#x2003;&#x2003;(1)wherein Rrepresents a hydrogen atom or a methyl group, Rrepresents a saturated or unsaturated hydrocarbon group having 1 to 20 carbon atoms, and the molecule may contain a hetero atom or a halogen atom,as an essential component and contains a remaining radical-polymerizable side-chain vinyl group in the molecule, wherein the composition comprises a thermally curable polymer (B) in an amount of 5 to 60 parts by weight per 100 parts by weight of the polymer (A).

Optical refractive index-modifying polymer composition, hologram recording material and method of controlling refractive index

A subject for the invention is to provide a method of refractive index regulation by which the refractive index of an optical polymer molding can be efficiently changed without necessitating a complicated step, such as the step of oxidizing beforehand, and which when used for producing an optical device, imparts excellent transparency thereto. Another subject is to provide a photochemically refractive-index-changing polymer or photochemically refractive-index-changing polymer composition for use in the method. The invention relates to a method of refractive index regulation characterized in that either a photochemically refractive-index-changing polymer which is a polymer of one or more monomers comprising an acrylic vinyl monomer represented by CH&#x2550;C(R)C(&#x2550;O)O&#x2014;R&#x2550;CH(wherein Ris hydrogen or methyl and Ris a saturated or unsaturated hydrocarbon group having 1-20 carbon atoms, provided that the monomer may have one or more heteroatoms and halogen atoms in the molecule) as an essential ingredient and which has radial-polymerizable side-chain vinyl groups remaining in the molecule or a composition containing this polymer is irradiated with a radiation, e.g., ultraviolet, to react the vinyl groups and thereby cause a density change so as to result in a refractive-index increase (&#x394;n) through the irradiation of 0.005 or more.

Photochemically refractive-index-changing polymer, photochemically refractive-index-changing polymer composition, and method of refractive index regulation

The present invention provides a pressure sensitive adhesive composition for optical members, which is excellent in durability, re-releasability and stress relaxation, as well as a pressure sensitive adhesive composition for optical members, which hardly increases adhesion after storage for a long time and does not leave a residual adhesive on glass upon disposal or repair. The pressure sensitive adhesive composition for optical members according to the present invention comprises 100 parts by weight of an acrylic polymer (A) having a weight-average molecular weight of 500,000 or more, containing at least 50 wt % alkyl (meth)acrylate having an alkyl group with 5 or more carbon atoms and 0.2 to 2 wt % unsaturated carboxylic acid as the monomer unit, 0.1 to 4 parts by weight of an acrylic polymer (B) having a weight-average molecular weight of 2,000 to 50,000, containing at least 70 wt % alkyl(meth)acrylate and 1 to 7 wt % unsaturated carboxylic acid as the monomer unit and having a higher carboxylic acid equivalent than that of the acrylic polymer (A), 0.01 to 1 part by weight of a silane coupling agent, and a crosslinking agent.

The base material for pressure-sensitive adhesive tape or sheet is constituted of a polyolefin based resin as the major component and is obtained by rolling by means of a calender having a measure capable of individually changing the rotational speed of each calender roll. Examples of the measure capable of individually changing the rotational speed of each calender roll include a measure provided with motors capable of individually driving their respective calender rolls and a measure provided with speed regulators capable of individually regulating their respective calender rolls. It may be employed that the number of calender rolls is four and that the roll arrangement is in the reverse L shape. It is preferable that the base material for pressure-sensitive adhesive tape or sheet contains an inorganic compound together with the polyolefin based resin.

Base material for pressure-sensitive adhesive tape or sheet, pressure-sensitive tape or sheet using the base material, and process of producing the base material

Disclosed are a pressure-sensitive adhesive composition comprising a reactive mixture of a relatively low molecular weight acrylic prepolymer containing highly reactive hydroxyl groups in the molecule thereof which is obtained by copolymerizing two alkyl acrylate monomers satisfying a specific relationship and, as a chain extender, a polyfunctional isocyanate mainly exhibiting bifunctionality; a pressure-sensitive adhesive composition comprising the above reactive mixture and a relatively high molecular weight polymer component; and pressure-sensitive adhesive sheets having a pressure-sensitive adhesive layer comprising those pressure-sensitive adhesive compositions. Because the molecular chain of the acrylic prepolymer is extended efficiently, the amount of an organic solvent required for viscosity adjustment can be decreased.

Growing community of inventors

Ibaraki, Japan

Yoshihide Kawaguchi